Enable testing with Django 2.1

testing with versions 1.11 and 2.0 is now only done on Python 3.6
while testing with 2.1 is performed on Python 3.5, 3.6 and 3.7.

NOTE: we're still testing on an old 3.7-dev because Travis CI
doesn't have the official 3.7 release yet. See:
travis-ci/travis-ci#9815

Author: atodorov

.travis.yml

@@ -1,26 +1,23 @@
 language: python
 python:
-  - 3.4
   - 3.5
   - 3.6
   - "3.7-dev"
 env:
   # note: latest versions first b/c the top-most is included in new
   # build stages if not specified
-  - DJANGO=2.0
-  - DJANGO=1.11
+  - DJANGO=2.1
 stages:
   - django_not_installed
   - django_is_installed
   - test
   - build_and_package_sanity
 matrix:
-  exclude:
-    # Python/Django combinations that aren't officially supported
-    - { python: "3.7-dev", env: DJANGO=1.11 }
   include:
     - { stage: django_not_installed, python: 3.6, env: TOXENV=django_not_installed }
     - { stage: django_is_installed, python: 3.6, env: TOXENV=django_is_installed }
+    - { stage: test, python: 3.6, env: DJANGO=2.0 }
+    - { stage: test, python: 3.6, env: DJANGO=1.11 }
     - { stage: test, python: 3.6, env: TOXENV=flake8 }
     - { stage: test, python: 3.6, env: TOXENV=pylint }
     - { stage: test, python: 3.6, env: TOXENV=readme }

tox.ini

@@ -8,8 +8,8 @@ envlist =
     flake8
     pylint
     readme
-    py{34,35,36}-django111
-    py{34,35,36,37}-django20
+    py{36}-django{111,20}
+    py{35,36,37}-django21
 
 [testenv]
 commands =
@@ -18,7 +18,8 @@ commands =
     flake8: flake8
     pylint: pylint --rcfile=tox.ini -d missing-docstring --ignore=tests pylint_django setup
     readme: python setup.py check --restructuredtext --strict
-    py{34,35,36,37}-django{111,20}: coverage run pylint_django/tests/test_func.py -v
+    py{36}-django{111,20}: coverage run pylint_django/tests/test_func.py -v
+    py{35,36,37}-django21: coverage run pylint_django/tests/test_func.py -v
     clean: find . -type f -name '*.pyc' -delete
     clean: find . -type d -name __pycache__ -delete
     clean: rm -rf build/ .cache/ dist/ .eggs/ pylint_django.egg-info/ .tox/
@@ -30,16 +31,15 @@ deps =
     readme: readme_renderer
     django111: Django>=1.11,<2.0
     django20: Django>=2.0,<2.1
-    py{37}: https://github.com/PyCQA/astroid/tarball/master#egg=astroid-master
-    py{37}: https://github.com/PyCQA/pylint/tarball/master#egg=pylint-master
-    py{34,35,36,37}: coverage
-    py{34,35,36,37}: djangorestframework
-    py{34,35,36,37}: django-model-utils
-    py{34,35,36,37}: django-tables2
-    py{34,35,36,37}: factory-boy
-    py{34,35,36,37}: psycopg2
-    py{34,35,36,37}: pylint-plugin-utils
-    py{34,35,36,37}: pytest
+    django21: Django>=2.1,<2.2
+    py{35,36,37}: coverage
+    py{35,36,37}: djangorestframework
+    py{35,36,37}: django-model-utils
+    py{35,36,37}: django-tables2
+    py{35,36,37}: factory-boy
+    py{35,36,37}: psycopg2
+    py{35,36,37}: pylint-plugin-utils
+    py{35,36,37}: pytest
 setenv =
     PIP_DISABLE_PIP_VERSION_CHECK = 1
     PYTHONPATH = .
@@ -52,6 +52,7 @@ whitelist_externals =
 DJANGO =
     1.11: django111
     2.0: django20
+    2.1: django21
 
 [flake8]
 max-line-length = 120